Gary Taubes basically says that one generally loses weight if and only if one eats fewer carbs, so this is some evidence for his claim (not strong evidence, since it’s consistent with most other models of weight loss too).
I would consider my experience zero evidence for or against Gary Taubes’ claim, since every model of weight loss predicts that anyone successfully doing what I did would lose weight. Sounds like a very strong claim, but the word “generally” is murky.
If you eat 3000 calories a day of fat and protein, wouldn’t you still gain weight?
Why would I? The only thing thermodynamics tells us is that calories place an upper bound on how much weight a person can maintain/gain. The actual amount of weight gained/lost depends on the operation of regulatory mechanisms.
I am not sure I am convinced by this argument, for the following reasons:
If you think of calorie content / thermodynamics as an upper bound on how much energy can be extracted from the food, you have to make an argument for what happens to the unused energy. Even if you are in a biochemical state where not all the energy is used, there is still energy floating around in your body in the form of carbohydrates, fat and protein. I can think of three possible mechanisms for what happens to this extra energy, and I am not convinced by any of them:
(1) Calories are excreted unused in their original form. However, I don’t think this happens to a meaningful extent
(2) If there is excess fat, nutrients are broken down to molecular constituents in a less efficient mechanism of cellular metabolism, ie, producing less ATP. This is a little more plausible than 1, but I think it would be evolutionary maladaptive to reduce the fuel efficiency of your engine unless it was absolutely necessary. Note that there are cases when the body does reduce the fuel efficiency (such as anaerobic metabolism), but I can’t see how this applies here
(3) (Added): If there is excess fat, the body begins to run processes that are not strictly necessary, thus using more fuel. However, I am not sure what these processes would be, or why they would be triggered by fat and not carbohydrates.
I find it plausible that increasing fat intake will help you lose weight due to regulatory pathways such as insulin, but I think this pathway operates almost exclusively through changes in appetite. I fail to see any arguments why we cannot use thermodynamics (calorie input/output) as a very good approximation of predicted weight change.
EDIT: This comment is being downvoted. I am happy to delete it if it doesn’t add to the discussion, but it would help me immensely if someone could explain why my reasoning is wrong...
EDIT2: I am not sure if I misunderstand the karma system, but I don’t think you are supposed to downvote someone for disagreeing with their conclusions. It is possible that I am wrong in my conclusions, but I don’t think this in itself is reason for downvoting.
If you disagree with my arguments, you can dissect them in the comments. Reasonable arguments with incorrect conclusions are still valuable in a discussion, and if you show why they are wrong, you will not only help me update my priors, but also help reveal a flaw in how non-trolls come to their beliefs. Hiding the comment prevents this. I don’t see any reason for downvoting, and I think the downvoters need to ask themselves if they are downvoting due to mood affiliation / cognitive bias.
(1) Calories are excreted unused in their original form. However, I don’t think this happens to a meaningful extent
(4) Calories are excreted unused not in their original form.
What do you think shit is made of? When dried out, it will burn—that’s calorific value right there. Everyone takes in more calories than they turn into heat and motion.
(5) Thermogenesis. If that’s impaired, you won’t burn as much fuel as it takes to maintain body temperature, but you may not even notice, because you’ll do other things to keep warm instead. Come to think of it, accumulating an insulating layer of fat will also dampen the effect.
CICO is about as helpful as MIMO—matter in, matter out. In is easy to measure, out not at all easy.
There is obviously thermodynamic energy in food which is not absorbed in the gastrointestinal tract. Fiber is an example of this. Energy which is not absorbed is not listed on the nutrition label of food. When I say ‘calories’, I mean the biochemically available energy in absorbed macronutrients such as fat, carbohydrates, protein and alcohol.
Nobody doubts that thermogenesis uses energy. This is a special case of my mechanism 3. It is part of the ‘energy used’. Again, if you want to convince me that you can eat 3000 calories of fat without gaining weight, you would have to make an argument that the proportion of fat in my diet has a causal effect on thermogenesis, ie, that my body will start running additional thermogenesis because I ate fat instead of carbohydrates.
Your claim that CICO is as helpful as MIMO is clearly ridiculous, and if you truly believe this, then supermodels eating tissue paper are more rational than you, as their beliefs will lead to more accurate predictions.
The point I am trying to make is that our body is an efficient engine due to evolutionary pressure, that energy doesn’t just disappear (if it did, we would observe large amounts of unmetabolized macronutrients in urine), and that even if CICO is not the whole picture, it explains a very large part of the variation in body weight observed in human populations
There is obviously thermodynamic energy in food which is not absorbed in the gastrointestinal tract. Fiber is an example of this. Energy which is not absorbed is not listed on the nutrition label of food.
On a previous occasion when this topic came up, I posted this anecdote.
Now, as you might imagine, there were medical reasons for that episode. Or rather, there were concurrent medical events with no obvious connection: acute ulcerative colitis, a disease of the large intestine only. Most nutrition is extracted by the stomach and small intestine, which were unaffected. So what was going on there? What made my digestive system so inefficient for several years following the initial attack?
So there’s a lot of room for variation in digestive efficiency.
(For those who know the last-resort treatment for ulcerative colitis, I’ll just add that I recovered without surgery.)
Your claim that CICO is as helpful as MIMO is clearly ridiculous
What is more ridiculous about MIMO than CICO? Conservation of matter, can’t argue with that.
and if you truly believe this, then supermodels eating tissue paper are more rational than you, as their beliefs will lead to more accurate predictions.
You don’t get to be a supermodel unless you can stay thin. Some people can, no-one doubts that, and some people just are, without taking any effort. And I’ll take Eliezer’s word that nothing has worked for him over anyone’s assertion that because they can’t see how something could happen, it doesn’t happen. CICO is only one part of the picture, and its abundantly clear from experiences of dieting that it’s of little explanatory value on its own, and of practical value to only a subset of people.
What is more ridiculous about MIMO than CICO? Conservation of matter, can’t argue with that.
OK, I see the point. But multicellular life evolved as thermodynamic engines, not as fusion plants. Over billions of years, cells were surviving based on how efficiently they could extract thermodynamic energy from macronutrients, to power intracellular processes. This is what we are optimized for. If we had been able to use fusion power in our evolutionary past, MIMO would be a more appropriate level at which to draw your map.
I fail to see any arguments why we cannot use thermodynamics (calorie input/output) as a very good approximation of predicted weight change.
It all depends on what you mean by “very good approximation.” There’s an entire cottage industry in medicine that revolves around developing weight prediction models; none of them get good results even assuming one knows much more data than simply calorie intake.
I suspect this is possibly the source of a few downvotes. Since this is superficially a site on rationality and science, every once in a while the doctrine of Calories In, Calories Out (CICO) rears it’s ugly head. People who have actually looked into the situation know that it’s a drastic oversimplification, but experience has shown it’s usually not worthwhile to convince adherents of CICO of the complexity of the problem.
Note that I don’t disagree with anything in that Mayo Clinic article. The point about “pounds of fat, muscle and water” is obviously true and does not contradict anything I said. The points about “metabolic rate” and “response to reduced calories” just seem to say that sometimes it is difficult to estimate the “calories out” part of the equation, and that it is endogenous to the system. This is also obviously true. I still find it difficult to believe that we can affect the metabolic rate to an extent that matters in the final analysis, based on the fat/protein/carbohydrate content of our diet..
Did I misunderstand your grandparent post? It sounded like you were looking for an explanation as to why CO is hard to quantify.
The points about “metabolic rate” and “response to reduced calories” just seem to say that sometimes it is difficult to estimate the “calories out” part of the equation, and that it is endogenous to the system.
I disagree that this is a fair rephrasing of the article. A correct rephrasing would be “It is always difficult to estimate the CO part of the equation.”
I still find it difficult to believe that we can affect the metabolic rate to an extent that matters in the final analysis, based on the fat/protein/carbohydrate content of our diet.
What would convince you otherwise? When I posted my grandparent response, I wasn’t in a position to link to the various body weight modelling studies that have been done, but I could do so if you’d think it might convince you.
OK. I’ll accept your rephrasing. Let us assume that “calories out” is always difficult to estimate and depends on a lot of factors such as muscle mass and total calorie intake.
I took the original comment to mean that we can eat very large amounts of fat and protein, because our bodies would somehow react, in response to the proportion of different nutrients in our diet, and change how efficiently we use energy. I find it difficult to believe that this would explain much of change in body weight. I find it much easier to believe that it would change our appetites and thus reduce calorie intake.
I am certainly willing to update my priors if someone convinces me of a plausible mechanism by which proportion of each nutrient alters efficiency of energy use..
(1) Calories are excreted unused in their original form. However, I don’t think this happens to a meaningful extent
I think this can actually happen to a very great extent depending on how much the person normally eats and burns, and how quickly they consume it, and is the main mechanism by which e.g. competitive eaters generally avoid becoming obese.
By which mechanism do these nutrients get excreted? Urine? Bile? Non-absorption?
My impression is that carbohydrates in urine is something that we only see to a significant extent when blood glucose concentration is at diabetic levels. Protein and fat in urine occurs, but it doesn’t seem to me that this happens to an extent where it can make a difference to the total energy picture
I don’t think excreting them through bile would work, the nutrients would just be reabsorbed further down the gastrointestinal tract.
It is possible that at very high intake levels, there is significant non-absorption of fat. Maybe this happens in competitive eaters, but I am not convinced it can explain much at fat intake levels seen in ordinary people..
(Bam.) So, under normal conditions you’re pretty efficient (~4% of your calories just get pooped back out), meaning that something like metabolic rate just swamps poop-energy-content as an interpersonal variable.
This article says that there is some non-absorption of fat in healthy people, and much greater non-absorption in people with cystic fibrosis.
If you want to convince me that I should consider this when I choose the fat/carbohydrate/protein content of my diet, you would have to make an argument that the percentage of fat that is not absorbed is a function of my diet, ie, causally related to what I choose to eat.
I’m not saying this is not theoretically possible, but my intuition tells me that the variation in absorbtion that is caused by diet, is unlikely to have a major impact in the final analysis
If you want to convince me that I should consider this when I choose the fat/carbohydrate/protein content of my diet, you would have to make an argument that the percentage of fat that is not absorbed is a function of my diet, ie, causally related to what I choose to eat.
So, Tim Ferris has done a couple of demonstrations where he ate about 20,000 calories in the course of 24 hours. The vast majority of that is not absorbed.
You may have had in mind the limited claim that macronutrient ratio has a small effect on the percentage of calories absorbed, which seems reasonable for normal macronutrient ratios, but quantity seems important, as well as more detailed chemical composition. For example, I don’t produce enough lactase to digest normal American quantities of milk consumption without chemical assistance, and so if I continued to drink a glass of milk each day, the amount of calories that made it into my bloodstream would be predictably lower than the amount of calories put into my mouth.
So while the CI calculation can be complex, it seems obvious to me that the amount of calories you put in your mouth is a good upper bound. (I don’t think this is seriously contested by anyone, but it’s worthwhile to establish that it’s not seriously contested.) The system dynamics may mean that in some cases a higher total number of calories in leads to a lower maintenance weight, and so just lowering intake is not always the right solution.
This comment is being downvoted. … it would help me immensely if someone could explain why my reasoning is wrong...
Comments which mention the importance of calories are reflexively downvoted around here.
I think many people are confused between what CICO actually says (your energy balance determines your weight loss or gain) and what their image of CICO—conveniently made out of straw—says (there is a magic fixed number of calories, if you eat less than that magic number you’ll lose weight).
I think many people are confused between what CICO actually says (your energy balance determines your weight loss or gain) and what their image of CICO—conveniently made out of straw
Typically the conversations are downvoted based on the actual expressed claims in those comments. Most people who make thermodynamics references do in fact say stupid things out of ignorance.
I had noticed this. Personally, I’m very confused about the causes-of-obesity issue. To me it’s obvious that if you eat less or burn more, you will lose weight. It’s complicated by regulatory mechanisms; eating less causes your body to conserve energy by slowing the metabolism, and physical exercise increases appetite. And I think it’s likely there are genetic set points that affect both body type (weight) and appetite. Then there’s the fidgeting thing. Then there are the low/high carb theories and studies where weight is modulated by changes in regulatory pathways, and the “fructose poisoning causes fatty liver causes metabolic dysfunction” theory. And stuff like “metabolic syndrome” and Type 2 diabetes. Then there are people who are fat and eat half what I do. In the end, I have no idea how the human body regulates weight and calorie intake, but my body seems to do it fine.
Think of weight regulation as a three-layered cake :-)
The bottom layer is physics and CICO holds. The only way to lose weight is to spend more energy than you consume.
The middle layer is biochemistry. CICO still holds, but the energy output is a function of a large number of inputs (from genetic makeup to what kind of food do you eat). All the metabolic issues, insulin, leptin, ketosis, etc. live here.
The top layer is the mind. CICO still holds and all the biochemical mechanisms from the middle layer still hold, but now we add all the mental stuff—preferences, compulsions, eating-for-comfort, anorexia, eating as a displacement mechanism, etc.
And the cherry on top is that people are different. They have different metabolisms which work in different ways, they react differently to the same stimuli. No solution works for everyone and it looks likely that no solution even works for most. The only way out is to personally experiment and find out what works for you, for your personal, unique, and strange body and mind.
And we haven’t even touched the question of whether weight is the right metric to use (consider the alternatives, e.g. body fat % or general health even understood in a limited sense as absence of disease and normal metabolic markers).
The only way to lose weight is to spend more energy than you consume.
Liposuction.
The laws of thermodynamics don’t require a fat cell to release lipids because you’re hungry or exercising; the fat cells can just physically not react until your muscles run out of glucose or your brain overrules your attempt to starve yourself to death. Similarly, there’s no rule that fat cells can’t die or shrink and the waste be dumped out through urine.
Thermodynamics is not any more useful than quantum mechanics in understanding obesity. It is moralizing disguised as an invocation of natural law.
Thermodynamics is not any more useful than quantum mechanics in understanding obesity. It is moralizing disguised as an invocation of natural law.
Obesity rates used to be low. They’re now higher. The most obvious changes are higher food availability (and different food availability, read refined sugar/high fructose corn syrup/superstimuli fast food deliciousness), and more sedentary lifestyles. There may be other subtler changes, like the permanent psychological effects of being exposed to food advertising from a young age, and a million things that we don’t know yet, but there’s something out there, in the physical world, that has changed. And it’s not liposuction–that, and gastic bypass surgery, etc, didn’t exist a hundred years ago–their invention apparently hasn’t reduced obesity rates.
In summary, people moralizing about how obesity is just “calories in calories out” aren’t doing anything to solve the problem. But saying that thermodynamics is “moralizing disguised as an invocation of natural law” is just pointing out how not to solve the problem–it’s not helpful either unless you suggest an alternate solution. Or a list of 20 different things to try, at least 1 of which should work for >99.9% of the population. Or a drug that can target some mysterious fat cell receptor to make them cooperatively release energy during exercise/dieting. Or a special diet that empirically does the same thing, even if no one knows how or why. Or a way to raise children so that they have the same obesity risk as children 200 years ago. Or a way to at least treat the negative cardiovascular health benefits of obesity and make it harmless. Or liposuction. Etc etc etc. I don’t think people will get so mad about “moralizing” when this problem has a better solution.
...Oh, and a society that doesn’t massively penalize people for being chubby as long as their cardiovascular health is good would be a massive step in the right direction. As a normal weight girl who used to train in the pool every day, but still spent most of high school thinking I was fat and unattractive because of media images of models, I have a particular pet peeve with this.
The most obvious changes are higher food availability (and different food availability, read refined sugar/high fructose corn syrup/superstimuli fast food deliciousness),
In previous centuries, people rich enough not to have to worry about calories were rarely fat, certainly not at anything like modern rates. Food types have changed. Calorie supply seems like as much a red herring as the number of pirates or global warming.
Here’s someone fat enough to be a circus freak one century earlier:
“Thermodynamics” doesn’t explain that change. Some significant number of people a century ago could afford to eat as many calories as they wanted. Also, are we supposing that the circus freak was exceptionally rich?
In previous centuries, people rich enough not to have to worry about calories were rarely fat, certainly not at anything like modern rates.
This statement surprises me. I had always heard that obesity was a sign of social status, but I never thought to wonder about the actual statistics for obesity among the rich. I’m finding statements like “common among the rich,” which suggests to me that rates are probably comparable to the modern American rate, but I’m not finding numbers.
It appears that medieval monks were obese at three times the rate of the general population [src], but I’m having trouble finding the actual paper or the actual rates.
Here’s someone fat enough to be a circus freak one century earlier:
And here’s a famously fat nobleman. I read recently about Dionysius of Heraclea, who grew so fat that he could not eat, and eventually so fat that he could not breathe. (There are several other examples there of people who grew too fat to move across the centuries, including a Roman senator who was only able to walk when two slaves carried his belly for him.)
A snippet of the linked article stands out. One Michael Edelman, weighing 1200 lb at his heaviest, in the end made serious attempts to lose weight. My emphasis:
After the sudden death of Walter Hudson [another notably fat person], with whom he had formed a long-distance friendship, Michael developed a pathological fear of eating. He rapidly lost several hundred pounds, taking nourishment only when spoon fed. At about 600 lbs, he literally starved to death.
Now, it’s clear from that article that all of these people ate massive amounts, but then, one has to ask why they did that. Just what are the causal connections here? What are the causal arrows going into the “overeating” node? To say “gluttony” is just giving a name to one’s ignorance and mistaking it for knowledge. What actually distinguishes someone to whom a triple chocolate muffin with chocolate sauce and a chocolate-coated chocolate flake on top with extra chocolate is a temptation to be resisted, from someone to whom it is not a temptation?
What other arrows are going into the “obese” node? What arrows are coming out of it and where do they point?
I don’t think anyone knows the answers to these questions.
Now, it’s clear from that article that all of these people ate massive amounts, but then, one has to ask why they did that.
The first place I would look is hunger and satiety hormones. It wouldn’t surprise me if their ability to tell themselves they’re full is broken, and so they’re hungry all the time, so they eat all the time.
I had always heard that obesity was a sign of social status
I’ve heard this of Africa, but not of Europe. The reason that in preindustrial times millers were stereotypically fat is because it was assumed they pilfered a portion of the corn that farmers brought to them for milling. Friars (think of “Friar Tuck”) were stereotypically fat because they lived well (or were thought to) by visibly freeloading on the community. Neither class was well thought of for this. Being fat was taken as a sign not of status, but of idleness, sloth, greed, and gluttony.
Neither class was well thought of for this. Being fat was taken as a sign not of status, but of idleness, sloth, greed, and gluttony.
So, nobles, merchants, monks, and millers were all more likely to be fat than farmers, and all were seen by farmers as idle, greedy, gluttonous sloths. It’s not clear to me why you think that means farmers saw them as having low social status, rather than resenting their high social status.
A famously fat nobleman? LIke, that was the fat guy from the seventeenth century?
I’m not sure. My point was more than Galen knew about people so fat Jerry Springer would want to put them on his show today, and the heaviest guy you see at a sci-fi convention is comparable to the heaviest guy you would see in the Roman Senate.
I’d be way happier with “this is the percentage of monks that were obese in 1400s Britain” to compare with “this is the percentage of Americans that were obese in 2000s America.” From the qualitative descriptions I’m seeing, the rich were obese at broadly similar levels to Americans today, and I’m having trouble finding quantitative descriptions. Are you aware of data I’m not aware of?
The trouble is that routine weighing of individuals wasn’t common until industrial times, records are spotty anyway, and so we’re forced to look at individual accounts in most cases. For example, Rubens painted lots of overweight women, so we know they were around, but statistics of an artist’s models says more about the artist than about the general population. Similarly, a 19 year old that weighs 500 pounds is a very rare event, even today. The primary reason we don’t call them fat freaks and put them in circuses is because making fun of abnormal people in person has become less acceptable, and if you do it on television you can find people that weigh more like a thousand pounds.
My point was more than Galen knew about people so fat Jerry Springer would want to put them on his show today, and the heaviest guy you see at a sci-fi convention is comparable to the heaviest guy you would see in the Roman Senate.
I am not sure the outliers (or the tails of the distribution in general) are relevant here. We know that there are metabolic disorders leading to obesity. It’s a pretty good bet that the 500-600 lbs people are metabolically different from the rest of the population and that was as true in the Roman times as it is now.
The real question is not whether the 500 lbs people existed in the olden times, sure they did. The real question is why does it seem that 250-300 lbs people were rare in pre-industrial ages and are rather common now (yes, I don’t know of good data on the prevalence of obesity before XIX century either...).
I don’t think it’s mostly a calorie availability issue. I don’t have a strong opinion on the cause, but if pressed I’d probably point to a confluence of factors including sedentary lifestyles, taste superstimulation and calorically dense foods (mostly refined carbs), stress, etc.
The real question is why does it seem that 250-300 lbs people were rare in pre-industrial ages and are rather common now (yes, I don’t know of good data on the prevalence of obesity before XIX century either...).
I agree that this is the real question; what surprised me was Eliezer’s confident empirical statement on a subject where all the weak data I have points in the opposite direction. It looks to me like the historical data suggests that calorie availability and sedentary lifestyles might be the primary explanations (and of the two, I would expect calorie availability to have a larger impact).
For comparison, this is what it takes to be the fat girl from the first decade of this century. She made the national news when she weighed 63 stone and had to be taken out through the wall of her house to go to hospital. 1 stone = 14 pounds.
Plenty of foods available today not available to our ancestors, such as semi-dwarf wheat.
Or Coke, for that matter.
But if the reason why we are fat and our ancestors were thin is that there are foods we have and they didn’t, and we don’t want to be fat, we can just not eat those foods. “[We are fatter than our ancestors because] food types have changed” only entails that you can’t affect your weight through your diet if you cannot choose to eat what your ancestors did.
Everything we eat has been bred for thousands of years. Does any of it have enough in common with our ancestors’ diets that “eat only that” can work?
I suppose one might look at what wild primates eat in the present day to answer that. Part of that is “smaller primates”, so that still might not be the way to go.
I meant “ancestors” on the timescale of one or two centuries (the time it took for the prevalence of obesity to rise from negligible to sizeable), not megayears. By “food types have changed” EY was referring to (I assume) availability of industrial superstimulus foodstuffs full of high-fructose corn syrup and whatnot.
Ok, I had thought this was going in the direction of the whole paleo thing. Eating as we ate a couple of centuries ago looks much more doable, at the individual level. (Changing the whole society would be a whole different thing.) But perhaps “eat food, mostly plants, not too much” is already one of the things EY has tried?
If you can eat “not too much” without your fat cells starving you to death, you’re probably already thin. I haven’t tried “mostly plants” because it’s vastly underspecified and I’m not particularly interested in being told afterward that I ate the wrong plants.
But perhaps “eat food, mostly plants, not too much” is already one of the things EY has tried?
Probably he has; but, unless the fraction of “metabolically disprivileged” people like him has been rising a lot in the past couple centuries, I guess that the rising prevalence of obesity means there are a sizeable number of people who haven’t tried that (seriously enough).
A simpler solution is just taking a piss. But do you really want to go into highly specific and precise definitions which take care of all technicalities? I don’t think you have anything to win there.
The laws of thermodynamics don’t require a fat cell to release lipids
No they don’t. But they require you to lose mass. Notably, CICO does not claim you’ll lose fat—it claims you’ll lose weight and in most cases some of that weight will come from fat and some from muscle.
Thermodynamics is not any more useful than quantum mechanics in understanding obesity.
I disagree.
I think it was Taubes who compared CICO to telling an alcoholic that it’s drinking alcohol that makes him an alcoholic. He used it as a put-down, but I’m totally fine with the metaphor. Understanding that is only the first step on a long and twisty road, but you have to make it. Otherwise people tend to believe that alcoholism can be fixed by, say, switching to drinking port from drinking whisky, or that as long as they take supplement X they can eat all they want.
I think for you (and many other people) CICO became associated with a moralizing stance of “you just need to exercise self-control to stop shoving things into your mouth and then your weight will be fine”—but it says no such thing (and the stance is stupid, of course).
Thermodynamics does rule out the case where people claim to stay fat and metabolically active enough to be alive despite eating very few calories, which apparently has been a thing.
Thermodynamics is not any more useful than quantum mechanics in understanding obesity. It is moralizing disguised as an invocation of natural law.
Mm… I guess what this would be a case of I agree with the connotations of what you’re saying, but not with the explicitly stated form, which I’d say goes a bit too far. It’s probably more fair to say “energy-in—energy-spent—energy-out-without-being-spent = net delta energy” is part of the story, simply not the whole story.
It doesn’t illustrate the ways in which, say, one might become unwell/faint without sufficient energy-in of certain forms, even if one already has a reserve of energy that is theoretically available to their metabolism, for example.
It’s probably a useful thing to keep in mind when trying to diet, for those that can usefully diet that way, but it’s not the whole story, and other info (much of it perhaps not yet discovered) is also needed. (And certainly using it as an excuse to moralize/shame is completely invalid.)
But I wouldn’t call it useless, merely insufficient. What is useless is to pretend that there aren’t really important variables that can influence the extent to which one can usefully directly apply the thermodynamics. (People who ignore the ways that other variables can influence the ability to usefully apply the thermodynamic facts and thus condescendingly say “feh, just eat less and exercise more, this is sufficient advice for all people in all circumstances” are, of course, being poopyheads.)
The only way to lose weight is to spend more energy than you consume.
Depending on what you mean by “consume”, that statement is false.
What about a converse statement?
Over the long term, an obese person can consume less energy than she expends while maintaining her weight and body form.
I’m confident this statement would be untrue in practice. Sure, the person could undergo reverse-liposuction, or retain more and more and more water, or have a fusion reactor in her spleen, but the laws of thermodynamics restrict possible scenarios to implausible ones.
The laws of thermodynamics don’t require a fat cell to release lipids because you’re hungry or exercising; the fat cells can just physically not react until your muscles run out of glucose or your brain overrules your attempt to starve yourself to death.
They don’t, but the reason we evolved fat cells in the first place was that they released lipids allowing our ancestors to survive during periods of scarcity who otherwise wouldn’t have. Of course there may be people for whom this mechanism is broken, but I doubt that John Walker, who claims to have lost a sizeable fraction of his body weight without surgery and not gained it back for decades, is lying.
I can’t think of any way to answer you correctly and yet also briefly, because Taubes’s ideas are not easy, at least not easy for me, to put into a nutshell.
Therefore what I am about to say should be taken as no more than a very crude, and greatly exaggerated, approximation of Taubes’s theory. Here it is: if you eat more carbs, you turn yourself into a Zucker rat. If you eat fewer carbs, you stop being a Zucker rat.
What is a Zucker rat? I’ll let Taubes describe the Zucker rat:
These rats, like Mayer’s mice, are genetically predisposed to get fat. When Zucker rats are put on a calorie-restricted diet from the moment they’re weaned from their mothers’ milk, they don’t end up leaner than their littermates who are allowed to eat as much as they want. They end up fatter. They may weigh a little less, but they have just as much or even more body fat. Even if they want to be gluttons, which they assuredly do, they can’t, and they still get even fatter than they would have had they never been put on a diet. On the other hand, their muscles and organs, including their brains and kidneys, are smaller than they’d otherwise be. Just as the muscles in Mayer’s mice “melted away” when starved, the muscles and organs in these semi-starved Zucker rats are “significantly reduced” in size compared with those fat littermates who get to eat freely. “In order to develop this obese body composition in the face of calorie restriction,” wrote the researcher who reported this observation in 1981, “several developing organ systems in the obese rats [are] compromised.” Let’s think about this for a second. If a baby rat that is genetically programmed to become obese is put on a diet from the moment it’s weaned, so it can eat no more than a lean rat would eat, if that, and can never eat as much as it would like, it responds by compromising its organs and muscles to satisfy its genetic drive to grow fat. It’s not just using the energy it would normally expend in day-to-day activity to grow fat; it’s taking the materials and the energy it would normally dedicate to building its muscles, organs, and even its brain and using that.
Briefly and crudely, carbs affect insulin, insulin affects how greedy and stingy the fat cells are. Greedy fat cells grab energy-carrying molecules, effectively starving the rest of the body. Stingy fat cells are reluctant to let go of the energy they’ve stored, keeping the rest of the body starved. A starved body is simultaneously hungry and lethargic, for obvious reasons. This in effect reverses the usual causal picture. Greedy stingy fat cells cause a person to feel hungry and lethargic, which causes a person to be inactive and eat a lot. The picture that most people have in their minds is the reverse: a person who eats a lot and who exercises little will, as a consequence of these two vices, get fat. Taubes argues that these so-called vices are a symptom of starvation, which is caused by fat cells hoarding energy, which in turn is caused primarily by high insulin. To break the vicious cycle, cut out the part of the food which spikes insulin, and that is primarily the carbs, and specifically certain kinds of carbs which are rapidly digested.
To repeat, while I’m trying to give the best answer I can, it’s only an approximation of his argument.
Taubes wrote a 600-page book on the science, most of it involving humans. I’m out of my depth at this point—you would need to consult the book, either Good Calories Bad Calories, or one he wrote more recently for a wider audience that seriously trims back on the science. But if you want the science you want the earlier, bigger book.
The amazing thing (to me) is that Taubes’ two books are not original or personal studies, nor does he claim otherwise. Instead, they are exhaustive reviews of the published dietary research, in which he looks at what was found, and the conclusions that should be drawn. It is (in my opinion) one of the most egregious examples of confirmation bias that the establishment researchers and the government (USA) chose to conclude from these same studies those things that supported their established views, in spite of their own evidence to the contrary. I conclude that adoption of Taubes’ findings into our lifestyles would have more positive impact on healthcare (at least, in the USA) than anything else I know. I acknowledge that SIAI President Michael Vassar has said to me: “I met Taubes and he seemed (almost certainly) sincere but not all that bright. Definitely not very erudite and not all that good at philosophy of science.” I suggest that readers review Taubes’ credientials and determine, as I have, whether he is likely qualified both to understand and to write about the topic. I have been an Atkins devotee for years, and my chemistries reflect Taubes’ conclusions (anecdotal). I acknowledge that some very intelligent people (e.g. Yudkowsky) believe that some particular individuals are mysteriously “metabolically challenged”, and may respond differently, although I am not aware of the studies to confirm this.
I’m not a nutritionist, but the theory as I understand it is that shifting the balance of calories away from carbohydrates primes your metabolism by changing the pattern of insulin secretion, making your body more likely to break down its stored fats in order to keep blood glucose levels up.
High-fat, high-protein foods also tend to feel more filling for a given number of calories, and leafy vegetables are physically bulkier, which might also contribute to their perception as less fattening.
Gary Taubes basically says that one generally loses weight if and only if one eats fewer carbs, so this is some evidence for his claim (not strong evidence, since it’s consistent with most other models of weight loss too).
I would consider my experience zero evidence for or against Gary Taubes’ claim, since every model of weight loss predicts that anyone successfully doing what I did would lose weight. Sounds like a very strong claim, but the word “generally” is murky.
Um… Is that logical? If you eat 3000 calories a day of fat and protein, wouldn’t you still gain weight?
Why would I? The only thing thermodynamics tells us is that calories place an upper bound on how much weight a person can maintain/gain. The actual amount of weight gained/lost depends on the operation of regulatory mechanisms.
I am not sure I am convinced by this argument, for the following reasons:
If you think of calorie content / thermodynamics as an upper bound on how much energy can be extracted from the food, you have to make an argument for what happens to the unused energy. Even if you are in a biochemical state where not all the energy is used, there is still energy floating around in your body in the form of carbohydrates, fat and protein. I can think of three possible mechanisms for what happens to this extra energy, and I am not convinced by any of them:
(1) Calories are excreted unused in their original form. However, I don’t think this happens to a meaningful extent
(2) If there is excess fat, nutrients are broken down to molecular constituents in a less efficient mechanism of cellular metabolism, ie, producing less ATP. This is a little more plausible than 1, but I think it would be evolutionary maladaptive to reduce the fuel efficiency of your engine unless it was absolutely necessary. Note that there are cases when the body does reduce the fuel efficiency (such as anaerobic metabolism), but I can’t see how this applies here
(3) (Added): If there is excess fat, the body begins to run processes that are not strictly necessary, thus using more fuel. However, I am not sure what these processes would be, or why they would be triggered by fat and not carbohydrates.
I find it plausible that increasing fat intake will help you lose weight due to regulatory pathways such as insulin, but I think this pathway operates almost exclusively through changes in appetite. I fail to see any arguments why we cannot use thermodynamics (calorie input/output) as a very good approximation of predicted weight change.
EDIT: This comment is being downvoted. I am happy to delete it if it doesn’t add to the discussion, but it would help me immensely if someone could explain why my reasoning is wrong...
EDIT2: I am not sure if I misunderstand the karma system, but I don’t think you are supposed to downvote someone for disagreeing with their conclusions. It is possible that I am wrong in my conclusions, but I don’t think this in itself is reason for downvoting.
If you disagree with my arguments, you can dissect them in the comments. Reasonable arguments with incorrect conclusions are still valuable in a discussion, and if you show why they are wrong, you will not only help me update my priors, but also help reveal a flaw in how non-trolls come to their beliefs. Hiding the comment prevents this. I don’t see any reason for downvoting, and I think the downvoters need to ask themselves if they are downvoting due to mood affiliation / cognitive bias.
(4) Calories are excreted unused not in their original form.
What do you think shit is made of? When dried out, it will burn—that’s calorific value right there. Everyone takes in more calories than they turn into heat and motion.
(5) Thermogenesis. If that’s impaired, you won’t burn as much fuel as it takes to maintain body temperature, but you may not even notice, because you’ll do other things to keep warm instead. Come to think of it, accumulating an insulating layer of fat will also dampen the effect.
CICO is about as helpful as MIMO—matter in, matter out. In is easy to measure, out not at all easy.
There is obviously thermodynamic energy in food which is not absorbed in the gastrointestinal tract. Fiber is an example of this. Energy which is not absorbed is not listed on the nutrition label of food. When I say ‘calories’, I mean the biochemically available energy in absorbed macronutrients such as fat, carbohydrates, protein and alcohol.
Nobody doubts that thermogenesis uses energy. This is a special case of my mechanism 3. It is part of the ‘energy used’. Again, if you want to convince me that you can eat 3000 calories of fat without gaining weight, you would have to make an argument that the proportion of fat in my diet has a causal effect on thermogenesis, ie, that my body will start running additional thermogenesis because I ate fat instead of carbohydrates.
Your claim that CICO is as helpful as MIMO is clearly ridiculous, and if you truly believe this, then supermodels eating tissue paper are more rational than you, as their beliefs will lead to more accurate predictions.
The point I am trying to make is that our body is an efficient engine due to evolutionary pressure, that energy doesn’t just disappear (if it did, we would observe large amounts of unmetabolized macronutrients in urine), and that even if CICO is not the whole picture, it explains a very large part of the variation in body weight observed in human populations
On a previous occasion when this topic came up, I posted this anecdote.
Now, as you might imagine, there were medical reasons for that episode. Or rather, there were concurrent medical events with no obvious connection: acute ulcerative colitis, a disease of the large intestine only. Most nutrition is extracted by the stomach and small intestine, which were unaffected. So what was going on there? What made my digestive system so inefficient for several years following the initial attack?
So there’s a lot of room for variation in digestive efficiency.
(For those who know the last-resort treatment for ulcerative colitis, I’ll just add that I recovered without surgery.)
What is more ridiculous about MIMO than CICO? Conservation of matter, can’t argue with that.
You don’t get to be a supermodel unless you can stay thin. Some people can, no-one doubts that, and some people just are, without taking any effort. And I’ll take Eliezer’s word that nothing has worked for him over anyone’s assertion that because they can’t see how something could happen, it doesn’t happen. CICO is only one part of the picture, and its abundantly clear from experiences of dieting that it’s of little explanatory value on its own, and of practical value to only a subset of people.
OK, I see the point. But multicellular life evolved as thermodynamic engines, not as fusion plants. Over billions of years, cells were surviving based on how efficiently they could extract thermodynamic energy from macronutrients, to power intracellular processes. This is what we are optimized for. If we had been able to use fusion power in our evolutionary past, MIMO would be a more appropriate level at which to draw your map.
It all depends on what you mean by “very good approximation.” There’s an entire cottage industry in medicine that revolves around developing weight prediction models; none of them get good results even assuming one knows much more data than simply calorie intake.
I suspect this is possibly the source of a few downvotes. Since this is superficially a site on rationality and science, every once in a while the doctrine of Calories In, Calories Out (CICO) rears it’s ugly head. People who have actually looked into the situation know that it’s a drastic oversimplification, but experience has shown it’s usually not worthwhile to convince adherents of CICO of the complexity of the problem.
Here is a list of some violations of CICO.
Thank you, that was helpful.
Note that I don’t disagree with anything in that Mayo Clinic article. The point about “pounds of fat, muscle and water” is obviously true and does not contradict anything I said. The points about “metabolic rate” and “response to reduced calories” just seem to say that sometimes it is difficult to estimate the “calories out” part of the equation, and that it is endogenous to the system. This is also obviously true. I still find it difficult to believe that we can affect the metabolic rate to an extent that matters in the final analysis, based on the fat/protein/carbohydrate content of our diet..
Did I misunderstand your grandparent post? It sounded like you were looking for an explanation as to why CO is hard to quantify.
I disagree that this is a fair rephrasing of the article. A correct rephrasing would be “It is always difficult to estimate the CO part of the equation.”
What would convince you otherwise? When I posted my grandparent response, I wasn’t in a position to link to the various body weight modelling studies that have been done, but I could do so if you’d think it might convince you.
OK. I’ll accept your rephrasing. Let us assume that “calories out” is always difficult to estimate and depends on a lot of factors such as muscle mass and total calorie intake.
I took the original comment to mean that we can eat very large amounts of fat and protein, because our bodies would somehow react, in response to the proportion of different nutrients in our diet, and change how efficiently we use energy. I find it difficult to believe that this would explain much of change in body weight. I find it much easier to believe that it would change our appetites and thus reduce calorie intake.
I am certainly willing to update my priors if someone convinces me of a plausible mechanism by which proportion of each nutrient alters efficiency of energy use..
I think this can actually happen to a very great extent depending on how much the person normally eats and burns, and how quickly they consume it, and is the main mechanism by which e.g. competitive eaters generally avoid becoming obese.
By which mechanism do these nutrients get excreted? Urine? Bile? Non-absorption?
My impression is that carbohydrates in urine is something that we only see to a significant extent when blood glucose concentration is at diabetic levels. Protein and fat in urine occurs, but it doesn’t seem to me that this happens to an extent where it can make a difference to the total energy picture
I don’t think excreting them through bile would work, the nutrients would just be reabsorbed further down the gastrointestinal tract.
It is possible that at very high intake levels, there is significant non-absorption of fat. Maybe this happens in competitive eaters, but I am not convinced it can explain much at fat intake levels seen in ordinary people..
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1793018/
(Bam.) So, under normal conditions you’re pretty efficient (~4% of your calories just get pooped back out), meaning that something like metabolic rate just swamps poop-energy-content as an interpersonal variable.
This article says that there is some non-absorption of fat in healthy people, and much greater non-absorption in people with cystic fibrosis.
If you want to convince me that I should consider this when I choose the fat/carbohydrate/protein content of my diet, you would have to make an argument that the percentage of fat that is not absorbed is a function of my diet, ie, causally related to what I choose to eat.
I’m not saying this is not theoretically possible, but my intuition tells me that the variation in absorbtion that is caused by diet, is unlikely to have a major impact in the final analysis
So, Tim Ferris has done a couple of demonstrations where he ate about 20,000 calories in the course of 24 hours. The vast majority of that is not absorbed.
You may have had in mind the limited claim that macronutrient ratio has a small effect on the percentage of calories absorbed, which seems reasonable for normal macronutrient ratios, but quantity seems important, as well as more detailed chemical composition. For example, I don’t produce enough lactase to digest normal American quantities of milk consumption without chemical assistance, and so if I continued to drink a glass of milk each day, the amount of calories that made it into my bloodstream would be predictably lower than the amount of calories put into my mouth.
So while the CI calculation can be complex, it seems obvious to me that the amount of calories you put in your mouth is a good upper bound. (I don’t think this is seriously contested by anyone, but it’s worthwhile to establish that it’s not seriously contested.) The system dynamics may mean that in some cases a higher total number of calories in leads to a lower maintenance weight, and so just lowering intake is not always the right solution.
Comments which mention the importance of calories are reflexively downvoted around here.
I think many people are confused between what CICO actually says (your energy balance determines your weight loss or gain) and what their image of CICO—conveniently made out of straw—says (there is a magic fixed number of calories, if you eat less than that magic number you’ll lose weight).
Typically the conversations are downvoted based on the actual expressed claims in those comments. Most people who make thermodynamics references do in fact say stupid things out of ignorance.
My limited experience—that is, actual empirical data available to me—suggests this is not the case when the topic is CICO.
Most people who mention dieting or human metabolism do in fact say stupid things out of ignorance.
I had noticed this. Personally, I’m very confused about the causes-of-obesity issue. To me it’s obvious that if you eat less or burn more, you will lose weight. It’s complicated by regulatory mechanisms; eating less causes your body to conserve energy by slowing the metabolism, and physical exercise increases appetite. And I think it’s likely there are genetic set points that affect both body type (weight) and appetite. Then there’s the fidgeting thing. Then there are the low/high carb theories and studies where weight is modulated by changes in regulatory pathways, and the “fructose poisoning causes fatty liver causes metabolic dysfunction” theory. And stuff like “metabolic syndrome” and Type 2 diabetes. Then there are people who are fat and eat half what I do. In the end, I have no idea how the human body regulates weight and calorie intake, but my body seems to do it fine.
Well, it is complicated.
Think of weight regulation as a three-layered cake :-)
The bottom layer is physics and CICO holds. The only way to lose weight is to spend more energy than you consume.
The middle layer is biochemistry. CICO still holds, but the energy output is a function of a large number of inputs (from genetic makeup to what kind of food do you eat). All the metabolic issues, insulin, leptin, ketosis, etc. live here.
The top layer is the mind. CICO still holds and all the biochemical mechanisms from the middle layer still hold, but now we add all the mental stuff—preferences, compulsions, eating-for-comfort, anorexia, eating as a displacement mechanism, etc.
And the cherry on top is that people are different. They have different metabolisms which work in different ways, they react differently to the same stimuli. No solution works for everyone and it looks likely that no solution even works for most. The only way out is to personally experiment and find out what works for you, for your personal, unique, and strange body and mind.
And we haven’t even touched the question of whether weight is the right metric to use (consider the alternatives, e.g. body fat % or general health even understood in a limited sense as absence of disease and normal metabolic markers).
So yeah, complicated it is.
Liposuction.
The laws of thermodynamics don’t require a fat cell to release lipids because you’re hungry or exercising; the fat cells can just physically not react until your muscles run out of glucose or your brain overrules your attempt to starve yourself to death. Similarly, there’s no rule that fat cells can’t die or shrink and the waste be dumped out through urine.
Thermodynamics is not any more useful than quantum mechanics in understanding obesity. It is moralizing disguised as an invocation of natural law.
Obesity rates used to be low. They’re now higher. The most obvious changes are higher food availability (and different food availability, read refined sugar/high fructose corn syrup/superstimuli fast food deliciousness), and more sedentary lifestyles. There may be other subtler changes, like the permanent psychological effects of being exposed to food advertising from a young age, and a million things that we don’t know yet, but there’s something out there, in the physical world, that has changed. And it’s not liposuction–that, and gastic bypass surgery, etc, didn’t exist a hundred years ago–their invention apparently hasn’t reduced obesity rates.
In summary, people moralizing about how obesity is just “calories in calories out” aren’t doing anything to solve the problem. But saying that thermodynamics is “moralizing disguised as an invocation of natural law” is just pointing out how not to solve the problem–it’s not helpful either unless you suggest an alternate solution. Or a list of 20 different things to try, at least 1 of which should work for >99.9% of the population. Or a drug that can target some mysterious fat cell receptor to make them cooperatively release energy during exercise/dieting. Or a special diet that empirically does the same thing, even if no one knows how or why. Or a way to raise children so that they have the same obesity risk as children 200 years ago. Or a way to at least treat the negative cardiovascular health benefits of obesity and make it harmless. Or liposuction. Etc etc etc. I don’t think people will get so mad about “moralizing” when this problem has a better solution.
...Oh, and a society that doesn’t massively penalize people for being chubby as long as their cardiovascular health is good would be a massive step in the right direction. As a normal weight girl who used to train in the pool every day, but still spent most of high school thinking I was fat and unattractive because of media images of models, I have a particular pet peeve with this.
In previous centuries, people rich enough not to have to worry about calories were rarely fat, certainly not at anything like modern rates. Food types have changed. Calorie supply seems like as much a red herring as the number of pirates or global warming.
Here’s someone fat enough to be a circus freak one century earlier:
http://www.coolcrack.com/2011/06/fat-circus-freak-century-ago.html
“Thermodynamics” doesn’t explain that change. Some significant number of people a century ago could afford to eat as many calories as they wanted. Also, are we supposing that the circus freak was exceptionally rich?
This statement surprises me. I had always heard that obesity was a sign of social status, but I never thought to wonder about the actual statistics for obesity among the rich. I’m finding statements like “common among the rich,” which suggests to me that rates are probably comparable to the modern American rate, but I’m not finding numbers.
It appears that medieval monks were obese at three times the rate of the general population [src], but I’m having trouble finding the actual paper or the actual rates.
And here’s a famously fat nobleman. I read recently about Dionysius of Heraclea, who grew so fat that he could not eat, and eventually so fat that he could not breathe. (There are several other examples there of people who grew too fat to move across the centuries, including a Roman senator who was only able to walk when two slaves carried his belly for him.)
A snippet of the linked article stands out. One Michael Edelman, weighing 1200 lb at his heaviest, in the end made serious attempts to lose weight. My emphasis:
Now, it’s clear from that article that all of these people ate massive amounts, but then, one has to ask why they did that. Just what are the causal connections here? What are the causal arrows going into the “overeating” node? To say “gluttony” is just giving a name to one’s ignorance and mistaking it for knowledge. What actually distinguishes someone to whom a triple chocolate muffin with chocolate sauce and a chocolate-coated chocolate flake on top with extra chocolate is a temptation to be resisted, from someone to whom it is not a temptation?
What other arrows are going into the “obese” node? What arrows are coming out of it and where do they point?
I don’t think anyone knows the answers to these questions.
The first place I would look is hunger and satiety hormones. It wouldn’t surprise me if their ability to tell themselves they’re full is broken, and so they’re hungry all the time, so they eat all the time.
That’s also what The Hacker’s Diet says.
I’ve heard this of Africa, but not of Europe. The reason that in preindustrial times millers were stereotypically fat is because it was assumed they pilfered a portion of the corn that farmers brought to them for milling. Friars (think of “Friar Tuck”) were stereotypically fat because they lived well (or were thought to) by visibly freeloading on the community. Neither class was well thought of for this. Being fat was taken as a sign not of status, but of idleness, sloth, greed, and gluttony.
As indeed it continues to be taken to this day.
So, nobles, merchants, monks, and millers were all more likely to be fat than farmers, and all were seen by farmers as idle, greedy, gluttonous sloths. It’s not clear to me why you think that means farmers saw them as having low social status, rather than resenting their high social status.
I think that by “status” he meant what Yvain calls “social power”, whereas you mean what Yvain calls “structural power”.
A famously fat nobleman? LIke, that was the fat guy from the seventeenth century?
I’m not sure. My point was more than Galen knew about people so fat Jerry Springer would want to put them on his show today, and the heaviest guy you see at a sci-fi convention is comparable to the heaviest guy you would see in the Roman Senate.
I’d be way happier with “this is the percentage of monks that were obese in 1400s Britain” to compare with “this is the percentage of Americans that were obese in 2000s America.” From the qualitative descriptions I’m seeing, the rich were obese at broadly similar levels to Americans today, and I’m having trouble finding quantitative descriptions. Are you aware of data I’m not aware of?
The trouble is that routine weighing of individuals wasn’t common until industrial times, records are spotty anyway, and so we’re forced to look at individual accounts in most cases. For example, Rubens painted lots of overweight women, so we know they were around, but statistics of an artist’s models says more about the artist than about the general population. Similarly, a 19 year old that weighs 500 pounds is a very rare event, even today. The primary reason we don’t call them fat freaks and put them in circuses is because making fun of abnormal people in person has become less acceptable, and if you do it on television you can find people that weigh more like a thousand pounds.
I am not sure the outliers (or the tails of the distribution in general) are relevant here. We know that there are metabolic disorders leading to obesity. It’s a pretty good bet that the 500-600 lbs people are metabolically different from the rest of the population and that was as true in the Roman times as it is now.
The real question is not whether the 500 lbs people existed in the olden times, sure they did. The real question is why does it seem that 250-300 lbs people were rare in pre-industrial ages and are rather common now (yes, I don’t know of good data on the prevalence of obesity before XIX century either...).
I don’t think it’s mostly a calorie availability issue. I don’t have a strong opinion on the cause, but if pressed I’d probably point to a confluence of factors including sedentary lifestyles, taste superstimulation and calorically dense foods (mostly refined carbs), stress, etc.
I agree that this is the real question; what surprised me was Eliezer’s confident empirical statement on a subject where all the weak data I have points in the opposite direction. It looks to me like the historical data suggests that calorie availability and sedentary lifestyles might be the primary explanations (and of the two, I would expect calorie availability to have a larger impact).
For comparison, this is what it takes to be the fat girl from the first decade of this century. She made the national news when she weighed 63 stone and had to be taken out through the wall of her house to go to hospital. 1 stone = 14 pounds.
And are the kinds of food our ancestors ate no longer available today?
Plenty of foods available today not available to our ancestors, such as semi-dwarf wheat.
Or Coke, for that matter.
But if the reason why we are fat and our ancestors were thin is that there are foods we have and they didn’t, and we don’t want to be fat, we can just not eat those foods. “[We are fatter than our ancestors because] food types have changed” only entails that you can’t affect your weight through your diet if you cannot choose to eat what your ancestors did.
Everything we eat has been bred for thousands of years. Does any of it have enough in common with our ancestors’ diets that “eat only that” can work?
I suppose one might look at what wild primates eat in the present day to answer that. Part of that is “smaller primates”, so that still might not be the way to go.
I meant “ancestors” on the timescale of one or two centuries (the time it took for the prevalence of obesity to rise from negligible to sizeable), not megayears. By “food types have changed” EY was referring to (I assume) availability of industrial superstimulus foodstuffs full of high-fructose corn syrup and whatnot.
Ok, I had thought this was going in the direction of the whole paleo thing. Eating as we ate a couple of centuries ago looks much more doable, at the individual level. (Changing the whole society would be a whole different thing.) But perhaps “eat food, mostly plants, not too much” is already one of the things EY has tried?
If you can eat “not too much” without your fat cells starving you to death, you’re probably already thin. I haven’t tried “mostly plants” because it’s vastly underspecified and I’m not particularly interested in being told afterward that I ate the wrong plants.
Probably he has; but, unless the fraction of “metabolically disprivileged” people like him has been rising a lot in the past couple centuries, I guess that the rising prevalence of obesity means there are a sizeable number of people who haven’t tried that (seriously enough).
No.
English can be surprisingly ambiguous at times.
A simpler solution is just taking a piss. But do you really want to go into highly specific and precise definitions which take care of all technicalities? I don’t think you have anything to win there.
No they don’t. But they require you to lose mass. Notably, CICO does not claim you’ll lose fat—it claims you’ll lose weight and in most cases some of that weight will come from fat and some from muscle.
I disagree.
I think it was Taubes who compared CICO to telling an alcoholic that it’s drinking alcohol that makes him an alcoholic. He used it as a put-down, but I’m totally fine with the metaphor. Understanding that is only the first step on a long and twisty road, but you have to make it. Otherwise people tend to believe that alcoholism can be fixed by, say, switching to drinking port from drinking whisky, or that as long as they take supplement X they can eat all they want.
I think for you (and many other people) CICO became associated with a moralizing stance of “you just need to exercise self-control to stop shoving things into your mouth and then your weight will be fine”—but it says no such thing (and the stance is stupid, of course).
Thermodynamics does rule out the case where people claim to stay fat and metabolically active enough to be alive despite eating very few calories, which apparently has been a thing.
Mm… I guess what this would be a case of I agree with the connotations of what you’re saying, but not with the explicitly stated form, which I’d say goes a bit too far. It’s probably more fair to say “energy-in—energy-spent—energy-out-without-being-spent = net delta energy” is part of the story, simply not the whole story.
It doesn’t illustrate the ways in which, say, one might become unwell/faint without sufficient energy-in of certain forms, even if one already has a reserve of energy that is theoretically available to their metabolism, for example.
It’s probably a useful thing to keep in mind when trying to diet, for those that can usefully diet that way, but it’s not the whole story, and other info (much of it perhaps not yet discovered) is also needed. (And certainly using it as an excuse to moralize/shame is completely invalid.)
But I wouldn’t call it useless, merely insufficient. What is useless is to pretend that there aren’t really important variables that can influence the extent to which one can usefully directly apply the thermodynamics. (People who ignore the ways that other variables can influence the ability to usefully apply the thermodynamic facts and thus condescendingly say “feh, just eat less and exercise more, this is sufficient advice for all people in all circumstances” are, of course, being poopyheads.)
Depending on what you mean by “consume”, that statement is false.
What about a converse statement?
I’m confident this statement would be untrue in practice. Sure, the person could undergo reverse-liposuction, or retain more and more and more water, or have a fusion reactor in her spleen, but the laws of thermodynamics restrict possible scenarios to implausible ones.
They don’t, but the reason we evolved fat cells in the first place was that they released lipids allowing our ancestors to survive during periods of scarcity who otherwise wouldn’t have. Of course there may be people for whom this mechanism is broken, but I doubt that John Walker, who claims to have lost a sizeable fraction of his body weight without surgery and not gained it back for decades, is lying.
I can’t think of any way to answer you correctly and yet also briefly, because Taubes’s ideas are not easy, at least not easy for me, to put into a nutshell.
Therefore what I am about to say should be taken as no more than a very crude, and greatly exaggerated, approximation of Taubes’s theory. Here it is: if you eat more carbs, you turn yourself into a Zucker rat. If you eat fewer carbs, you stop being a Zucker rat.
What is a Zucker rat? I’ll let Taubes describe the Zucker rat:
I suppose the point is less that you can lose weight on 3000 carb-free calories a day, and more that you can’t lose weight if you’re eating carbs.
Just out of interest, what’s the proposed mechanism by which carbs turn us into Zucker rats?
Briefly and crudely, carbs affect insulin, insulin affects how greedy and stingy the fat cells are. Greedy fat cells grab energy-carrying molecules, effectively starving the rest of the body. Stingy fat cells are reluctant to let go of the energy they’ve stored, keeping the rest of the body starved. A starved body is simultaneously hungry and lethargic, for obvious reasons. This in effect reverses the usual causal picture. Greedy stingy fat cells cause a person to feel hungry and lethargic, which causes a person to be inactive and eat a lot. The picture that most people have in their minds is the reverse: a person who eats a lot and who exercises little will, as a consequence of these two vices, get fat. Taubes argues that these so-called vices are a symptom of starvation, which is caused by fat cells hoarding energy, which in turn is caused primarily by high insulin. To break the vicious cycle, cut out the part of the food which spikes insulin, and that is primarily the carbs, and specifically certain kinds of carbs which are rapidly digested.
To repeat, while I’m trying to give the best answer I can, it’s only an approximation of his argument.
Based on what I know about biochemistry and metabolism, that sounds reasonable. Have they done any studies on humans (not mice)?
Taubes wrote a 600-page book on the science, most of it involving humans. I’m out of my depth at this point—you would need to consult the book, either Good Calories Bad Calories, or one he wrote more recently for a wider audience that seriously trims back on the science. But if you want the science you want the earlier, bigger book.
The amazing thing (to me) is that Taubes’ two books are not original or personal studies, nor does he claim otherwise. Instead, they are exhaustive reviews of the published dietary research, in which he looks at what was found, and the conclusions that should be drawn. It is (in my opinion) one of the most egregious examples of confirmation bias that the establishment researchers and the government (USA) chose to conclude from these same studies those things that supported their established views, in spite of their own evidence to the contrary. I conclude that adoption of Taubes’ findings into our lifestyles would have more positive impact on healthcare (at least, in the USA) than anything else I know. I acknowledge that SIAI President Michael Vassar has said to me: “I met Taubes and he seemed (almost certainly) sincere but not all that bright. Definitely not very erudite and not all that good at philosophy of science.” I suggest that readers review Taubes’ credientials and determine, as I have, whether he is likely qualified both to understand and to write about the topic. I have been an Atkins devotee for years, and my chemistries reflect Taubes’ conclusions (anecdotal). I acknowledge that some very intelligent people (e.g. Yudkowsky) believe that some particular individuals are mysteriously “metabolically challenged”, and may respond differently, although I am not aware of the studies to confirm this.
I’m not a nutritionist, but the theory as I understand it is that shifting the balance of calories away from carbohydrates primes your metabolism by changing the pattern of insulin secretion, making your body more likely to break down its stored fats in order to keep blood glucose levels up.
High-fat, high-protein foods also tend to feel more filling for a given number of calories, and leafy vegetables are physically bulkier, which might also contribute to their perception as less fattening.